1. Field of the Invention
The present invention relates to a flash thermal transfer method of thermally transferring a melt ink layer onto a transfer medium by flashing a flash lamp and a flash thermal transfer apparatus for practicing the method.
2. Description of the Related Art
According to a known conventional transfer method, a stencil original is prepared by flashing a flash lamp, and hot melt ink is coated on the stencil original so as to transfer part of the hot melt ink corresponding to perforated portions of the stencil original onto a transfer medium.
A flash thermal transfer apparatus used for such transfer method has a pivot case mounted on its main body. A flash lamp is mounted on this pivot case, and a press plate having a cushion member is arranged on the main body. The flash lamp is arranged in a light source chamber of the pivot case. An opening is formed in one surface (opposing the press plate) of the light source chamber. A transparent glass is attached to the opening. The cushion member is designed to cause the entire surfaces of a stencil original plate and an original or an original and a transparent sheet to be uniformly brought into tight contact with each other upon transfer.
when transfer is to be performed by using such a flash transfer apparatus, a stencil original plate is mounted on the outer surface of the transparent glass, and an original is placed on the cushion member of the press plate. The pivot case is then pivoted to sandwich the stencil original plate and the original between the transparent glass and the cushion member. In this state, the flash lamp is flashed to thermally melt portions of the stencil original plate corresponding to an image of the original, thereby forming an image as perforated portions. Subsequently, ink is squeezed from an ink tube in which hot melt ink is filled and is coated on another sheet, and the sheet is stacked on the inner surface of the original plate and is mounted on the transparent glass.
At the same time, a recording sheet is arranged on the cushion of the press plate, and the pivot case is pivoted in the same manner as described above so as to cause the original plate and the recording sheet to be arranged between the transparent glass and the cushion member and be brought into tight contact therewith. When the flash lamp is turned on in this state, an image corresponding to the image of the original plate is transferred onto the recording sheet, thus obtaining a copy.
In a method using the above-described apparatus, fine lines can not be reproduced faithfully to the image on an original, since a stencil plate has a stencil which has a perforative pattern corresponding to the image and formed by thermally melting a film, and this perforative pattern inevitably expands toward a peripheral portion of the image. In other words, the resolution is degraded.
In addition, when hot melt ink is coated on a stencil original plate and the hot melt ink is thermally transferred, operator's hands tend to be smeared with the ink and so does a transfer medium. Hence, this operation is difficult.
Moreover, a cushion member and a transparent glass are respectively arranged on the lower and upper surface sides of a transfer medium, so that transfer is performed by sandwiching the transfer medium between the transparent glass and the cushion member. This operation is very inefficient, and the transfer apparatus is increased in size and cost. The most significant drawback of the transfer method of sandwiching a transfer medium between a transparent glass and a cushion member is that a transfer medium is limited to paper and films.